polyp of vocal cord
参考答案：
声带息肉：是声带任克间隙局限性水肿、血管扩张或出血而形成的向外脱垂的白色或粉红色的椭圆形肿物，表面光滑。
John, you must get your room ________ after breakfast. [ ]
A. to be cleaned
B. to clean
C. cleaning
D. cleaned
Hospital staff burst into cheers after doctors completed a 20hour operation to have _________ one-year-old twins at the head.
A．isolated
B．separated
C．divided
D．removed
after breakfast. [ ]